The present inventive concept is related to memory systems, and more particularly, to memory systems performing refresh operations. The present inventive concept is related to methods of performing refresh operations in a memory system.
Portable electronic devices have become an important part of modern lifestyles. Digital cameras, MP3 players, cellular phones, PDAs, and the like are commonly used by many across a broad spectrum of personal and professional applications. Contemporary portable electronic devices include ever more sophisticated memory systems. Such memory systems may be configured around one or more types of memory cells. Memory cells may be generally classified as being volatile in their operating nature (e.g., DRAM and SRAM), or non-volatile (e.g., EEPROM, FRAM, PRAM, MRAM, and flash memory). Volatile memories lose stored data in the absence of applied power, while non-volatile memories are able to retain stored data even in the absence of applied power.
Stored data integrity is an important aspect of ensuring overall memory system reliability. That is, the value of constituent stored data must not unintentionally or unpredictably change over time within a memory system. However, maintaining data integrity is a significant challenge. Many environmental and operational factors common to conventional memory systems tend to change the state of stored data.